Header:
#ifndef HEADER_H_INCLUDED
#define HEADER_H_INCLUDED
int i[8];
#endif
Main:
#include <iostream>
#include <string>
#include "header.h"
using namespace std
int main(){
int *test;
string bits = "10011011";
*test = func(bits); // ERROR 2 HERE
//my goal here is to have a pointer in main that
//points to the 1 address of the global var array i
} //if im totally missing the point and there is a
//better way to do this please let me know
Function:
#include <iostream>
#include <string>
using namespace std
int *func(string str){
int l = str.size();
int *ptr;
for(int k=0; k < l; ++k){
i[k] = s[k] - '0';
}
*ptr = i; // ERROR 1 HERE
return ptr;
}
Hi all,
When I attempt to compile the above code, I get two errors as labeled. They are:
Error 1: invalid conversiopn from int* to int Error 2: invalid conversion from int to *int
It seems I must have a fundamental understanding of what I am working with here. Am I not setting *ptr to point at the first memory address of the array i[]? Why is the compiler telling me that I am trying to set the value of the pointer to the value of i[]? I want to set the value of the pointer to the ADDRESS of i[]. If I add an & I get the same error.
Error 2 obviously follows error 1. It is the same error, just backwards.
My question is, then, what the heck am I doing wrong when I am trying to point *ptr in func() at the array i[]? I DID try finding the answers elsewhere to no avail.
Thanks.
edit: this code is a rough transcription of the original (from another PC), so if you try to compile it and there are typos I apologize.
int *ptr;
declares a pointer to int
, so ptr
is a pointer: a variable that stores the memory location of some int
. Currently it doesn't point to anything in particular, just some random place in memory that you probably don't own.
*ptr
dereferences ptr
, so *ptr
is the int
that ptr
points to.
When you do *ptr = i;
you are attempting to set the int
pointed to by ptr
equal to i
, which is an array of 8 int
s. In this context, the array decays into a pointer to its first element, so you're attempting to set an int
equal to an int*
, hence the error.
This should just be ptr = i;
, but even that isn't necessary, since you could just return i;
and i
would decay into a pointer to the first element of the array.
Similarly, *test = func(bits);
attempts to set the int
pointed to by test
equal to the pointer returned by func
. It should just be test = func(bits);
, in which case the address that test
contains will become the one that func
returned. In this case test
will point to the first element of i
.
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